Last week, in response to the MPAA lawsuits against BitTorrent trackers, I wrote that it’s impossible to sue BitTorrent itself, because it is nothing but a communications protocol. Michael Madison was skeptical, which was a fair response given what little I had written on the subject. Let me say a bit more, to clarify.

Opponents of P2P technologies often make the rhetorical move of calling the thing they oppose a “network.” The word carries connotations – especially for nonexperts – of a physical contrivance that is operated by some organization. Think of the old phone system, or the electrical power grid. Somebody has to build and manage all that equipment. The implication is that there is somebody in charge who can supervise the use of the network. Read the plaintiffs’ briefs in the Grokster case and you’ll see many references to a “network” that is “operated” by the defendants.

Computer scientists sometimes use the word “network” to refer to something more virtual. Others are now using “network” in this sense, as when people talk about the social network of friendships among the residents of a small town. Nobody owns and operates the social network. There is nobody you can sue to shut it down, because it’s not a network in the same sense the power grid is.

A communications protocol is an agreement or convention about how computer systems can cooperate to accomplish some task. It isn’t owned or operated by anybody. (People might own copyrights or patents relating to a protocol, but let’s set aside that possibility for now.) There’s a sense in which English or any other human language is a kind of protocol that people use to cooperate with each other. Again: nobody owns, operates or controls the English language, and there is nobody you can sue to shut it down. This isn’t to say that you can’t punish misuses of English, such as fraud or criminal conspiracies that use the language; but punishing misuse is not the same as attacking the language itself.

Given a lawsuit about a particular technology, how can we tell whether that network is more like the power grid or more like a social network? Here I think the Grokster courts have gotten it right. Rather than arguing over what is a “network,” or what “network” means anyway, they looked at the nature of the technology and the defendant’s control or influence over it. That is, as lawyers say, a fact-intensive inquiry.

The MPAA, in suing the operators of BitTorrent trackers rather than trying to attack the BitTorrent protocol itself, seems to be recognizing this distinction. That in itself good news.

TinyP2P is a functional peer-to-peer file sharing application, written in fifteen lines of code, in the Python programming language. I wrote TinyP2P to illustrate the difficulty of regulating peer-to-peer applications. Peer-to-peer apps can be very simple, and any moderately skilled programmer can write one, so attempts to ban their creation would be fruitless.

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